Resistin is a cytokine which is a firstly-acknowledged mediator which induces an insulin resistance in an obese mouse. The cytokine belongs to the cysteine-rich proteins, is also known as resistin-like molecules (RELMs), and is related to regulation of an inflammatory process. Moreover, murine resistin is known to be related to an obesity-mediated insulin resistance and an occurrence of Type 2 diabetes.
In fact, the protein sequences of rat resistin and human resistin are identical by only about 60%. Rodents resistin is firstly expressed and secreted mainly in mature adipocytes, whereas human resistin is secreted mainly in peripheral blood mononuclear cell (PBMC), such as leukocytes, and macrophage. Although it has been revealed through various researches that the function of resistin is different between humans and rodents, the complete understanding therefor has not been reached yet due to a lack of information on resistin receptor and signal transduction pathway.
Human resistin is believed to be related to a recruitment of other immune cells and secretion of pro-inflammatory factor, and there have been continuous proofs that it is related to an inflammatory disease and arteriosclerosis regardless of the existence of insulin resistance.
A resistin which exists both in rat and human arteriosclerosis lesion is known as an inflammatory marker of arteriosclerosis in human, and also, is known to accelerate arteriosclerosis by activating monocyte. Accordingly, human resistin is believed to be a critical factor which regulates the monocyte leading an arteriosclerosis process.
Large parts of an inflammatory-related mechanism in human resistin seem to be regulated by an activity of nuclear factor kappa B (NF-κB) transcription factor, yet the signal transduction pathway which shows a pro-inflammatory effect of resistin is still unclear, and in addition, a receptor closely related to the resistin has not been confirmed yet.
Accordingly, a discovery of the receptor which directly interacts with human resistin as well as a clear understanding on its signal transduction pathway are required in the art.